The general purpose of the proposal research is to study the mechanisms involved in the regulation of lymphokine production and the regulation of the expression of lymphokine activity. Our previous studies have demonstrated serum lymphokine activity in certain human diseases associated with anergy. We have also shown that similar mechanisms are operative in the early stages of experimentally induced desensitization. Using desensitization as an experimental model, we will study the various stages of hyporesponsiveness with special attention to the various factors and components that contribute to diminished capacity to express manifestations of cellular immunity. These studies are designed to provide information both about the regulatory events in this form of immune response and about in vivo lymphokine activity in general.